feat: instrument analysis

frontend/src/App.tsx

@@ -100,7 +100,7 @@ function KeepAlivePage({ path, component: Component }: { path: string; component
 
 // Registers the instrument tab on navigation (renders nothing itself)
 function InstrumentRoute() {
-  const { id = 'EURUSD' } = useParams<{ id: string }>()
+  const { id = localStorage.getItem('last_instrument') || 'EURUSD' } = useParams<{ id: string }>()
   const { openInstrument } = useTabs()
   useEffect(() => { openInstrument(id.toUpperCase()) }, [id, openInstrument])
   return null
@@ -112,7 +112,7 @@ function InstrumentKeepAlive({ id }: { id: string }) {
   const isActive = location.pathname.toLowerCase() === `/instruments/${id.toLowerCase()}`
   return (
     <div className={isActive ? 'flex-1 min-h-0 overflow-y-auto' : 'hidden'}>
-      <InstrumentDashboard instrumentIdProp={id} />
+      <InstrumentDashboard instrumentIdProp={id} isVisible={isActive} />
     </div>
   )
 }
@@ -129,7 +129,7 @@ function NormalRoutes() {
   return (
     <div className={isInstrument ? 'hidden' : 'flex-1 overflow-auto'}>
       <Routes>
-        <Route path="/instruments" element={<Navigate to="/instruments/EURUSD" replace />} />
+        <Route path="/instruments" element={<Navigate to={`/instruments/${localStorage.getItem('last_instrument') || 'EURUSD'}`} replace />} />
         <Route path="/instruments/:id" element={<InstrumentRoute />} />
         {/* Legacy redirects */}
         <Route path="/impact"    element={<Navigate to="/market-events" replace />} />